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Wall

Brick Masonry Wall 

Bricks should be  of standard dimensions, sound, well-burnt  and  free from  defects, ringing clearly when  struck with  a trowel and as per approved  sample. The bond used should be English  with frog upwards. (No frog is provided in machine made bricks). At all corners alternate courses of brick  work  should be headers and stretchers respectively for effective bonding of the two walls. 

Excepting for the closer, no half bricks  bats must be allowed. Bricks  used  for face work  are to be uniform in colour and of the best shape. Verticality of  the walls, corners and jambs  should  be  frequently  checked with plumb bob.  RCC bed blocks should be provided  and properly  cured  where RCC beams/steel girders trusses rest on walls. Lintels should have  sufficient  bearing  on either sides. 

Gocxl liaison must be maintained between BIR and EIM staff so that cable conduit holes and chases  for electric/water supply/samtary fittings are placed  in correct position as  the masonry proceeds.  It is undesirable to make holes or damage walls later on after brick work is completed.  Chases in brick work should be cut  with  a sharp chisel not less  than 14 days after the brick work is completed. 

Further points to observe are given as under: 
  1. See that the bricks  are up to standard. Bats  and rejected  bricks  should be removed from the site of the work. 
  2. See that bricks  are well  soaked in  water before  use in all works (except masonry in mud mortar). 
  3. Get to know the details of the  bond required  and see that  correct  bond is used and that bricks  with  frogs are placed  with frog upwards. 
  4. Check  frequently for (i) Thickness of masonry,  (ii) verticality of walls,  (iii) verticality of comers, (iv) horizontdity of courses  and (v) breathing of joints. 
  5. See that  the joints  are of correct  thickness, thick joints are wasteful of mortar and a sign of slip-shod work. 
  6. Insist that proper  brick  enclosures arc made for  mixing  mortar. The enclosures should be of  small size keeping in view the quantity of mortar that is to be  mixed  at one time for use by masons within  about half an hour in case of cement mortar and two hours in case of lime-cement mortar and one working day-in case of lime mortar. 
Insist on mortar being  properly  proportioned.  Labour  invariably prefers  to mix mortar to  approximate proportion only and this  always  means lessening of the quantity of cement  or lime and on increase in the quantity of sand or Turk used Weigh the cement and mix with measured quarantines of sand and or sand and line. A convenient  quantity of plantar to mix  at one time is 100 litres. Depending on the specification of mortar  in use decide on whether one bag or 112 bag nestles are required  and use measuring boxes  of suitable size (40 x 35 x 25 cm) for measuring sand and other  constituents. One 50 kg cement bag may be taken  equal lo 35 litres. 
  1. In using coverlet mortar, insist on the minimum  quantity  of water  necessary to obtain a workable mortar being used. See that water  is added  slowly alter thorough dry mixing. In using lime mortar ensure that lime is first thoroughly slaked unless the lime used is hydrated bagged lime. 
  2. See that joints are correctly tilled. All brick-layers  prefer to lay bricks dry and  fill mortar from the top. Do not allow this in any circumstances. Have sample of masonry made in your presence and insist on all masonry  being in accordance with these samples. Any  masonry found being done by the wrong method  should be rejected  and dismantled in your presence. 
  3. See that water arrangements for tops of walls  at close of work are made where required. 
  4. Where pointing is in  the same mortar as for the brick work it is usual to specify that joints are struck as the  work proceeds. If additional pointing or plastering is required, rake the joints upto 10 mm soon  after the mortar has become slightly  stiff and before the close of the work. 
  5. Watch  that put-log holes do not damage the stability of masonry. 
  6. See all hold fasts  and holding down bolts before they are put in, to ensure that they are in accordance with specification and treated with preservative  against rust as specified. Always have them  put  into the work in your presence and ensure that they are properly surrounded  with mortar  or concrete as specified. Where bricks are laid in mud or lime mortar,  masonry round the hold fasts should be in cement mortar. 
  7. See that temporary  battens are provided  at the bottom of door frailness where culls do not exist.  Provide temporary diagonal  battens  where  openings are large. 
  8. See that no woodwork comes within 20 cm of flues. 
  9. Check  sizes of all rooms as scan as work  starts on superstructure. 
  10. It is comparatively easy to supervise masonry  work  when taus is below eye level. When the work gets above eye level it is much more necessary, but not so easy. Insist, therefore, on good ladders and good scaffolding being provided so that you can get about and  watch the masonry being done and examine it thoroughly. 
  11. See that frames are set forward to the thickness of plaster when required to be flush with  plastered surface. 
  12. See that all hidden  faces of woodwork are treated with preservative as specified before being placed in position.  Contractors are particularly  inclined to give such surfaces a  nominal coating only, Insist on the whole surface being  properly treated. 
  13. Work should  proceed at one level. Where, for any reason,  it becomes essential to  leave  any portion of work and proceeded with that  on either side of it, see that work is stepped back  and not  merely "toothed".  It is important to ensure that cross walls, returns, buttresses are built up course by course and carefully  bonded with the main walls. 
  14. All masons are careless about making sides of door and window openings truly  vertical.  Check these frequently as work goes up. Also see that lintels are horizontal and provided with adequate bearing. 

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